How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Christy Hammond Your Own Question
Christy Hammond
Christy Hammond, Bachelor of Science in Nursing
Category: Health
Satisfied Customers: 1529
Experience:  I have a B.S.N and more than 10 years of training and experience in patient care and education
Type Your Health Question Here...
Christy Hammond is online now
A new question is answered every 9 seconds

what does 20 percent lung capacity mean exactly

This answer was rated:

No Comment Added
Hi me44_4_, welcome to JA. Lung capacity is not a sufficient variable to base the prognosis of lung disease. "Normal" lung capacity varies by age, sex, weight, smoking history, and height and can be improved through pulmonary rehab and exercise. 20%lung capacity is used as a way to measure over time response to treatment, and really has the most value in context of several readings (is it going up, dropping precipitously...) If you'd like to share more about his disease I'd be happy to help you with any information that may help you in your decision making.
Customer: replied 9 years ago.
yes, i think i need more info, my husband thinks that he should do things regarding our finances, but i feel like it may leave me in the big fat red. as far a bills go if he should pass away. so the 20 persent lung capacity has me so worried. and i dont know really what that means..his dr. said about a year and 1/2 ago 2 years, but lung capacity was at 27 percent at that time so can you see my concern?i want to make wize decissions re: our debt's and really want to be more clear on what to expect, and later down the road what do i look for as far as home care and hospice. i never dealt with any of this ever.. so im scared and not confident in making decissions re: finances and the way i am in counseling due to this med. illness. cuz i cry alot and feel like i need to talk to someone and i feel like when i do talk to someone about this i dont know where to start and what to ask..
Customer: replied 9 years ago.
59 1/2 6 feet tall 190 lbs smoked 5 pac's a day for 10 years as a cop for 10 years
yes it has been going up and down mostly down a lot and up a little.. now does this help to get an answer from you or can we talk on the phone i will pay for this info.

I'm more than happy to give you any information I can, but I do need to know what disease his lungs are sucumbing to. It's obviously smoking related, but that could mean copd, lung cancer, pulmonary edema...

Patients can live for years with low lung capacity and with good treatment he can stop the drop in capacity and even bring it up quite a bit. I completely understand your fear-I just lost my mom to lung cancer-but with oxygen she lived two years with cancer, copd, and 15% lung capacity. Her lung capacity did not drop before she died, and we were aware of the number, but it was never used to make a prognosis.

You may need to start taking certain steps like hospice care , and I will be happy to give you guidance on the type of care he'll need etc but I need some information, or my answer will be based on the wrong information. Can you tell me his diagnosis is? Anything you know will help.

Customer: replied 9 years ago.
copd and emphaziema dianosed 15-17 yeasr ago
i have to go to work in one hour i will check my e-mail as soon as i get there.

His doctor's prognosis was made two years ago, based on what he saw then. To truly know his prognosis have him re-evaluated by the doctor and ask him for a new time frame. Factors that contribute most to mortality in lung disease are hypermucous secretion, acute respiratory infections, and cardiac co-morbidity (the presence of heart disease along with the lung disease). For now assume that your doctor's prognosis is accurate and he may be in the end stage of the disease. There are steps you can take to prepare for future needs.

He may or may not need home care. Some patients with lung disease will have a crisis that will negate the need for home care. Others will need anything from nursing to physical therapy to 24 hour care. If he is currently living independently with your assistance, and you are able to comfortably provide for his needs it may be several months before he needs more care. If you are becoming fatigued by his care you should set up assistance now. It does not have to be 24 hour or even 12 hour care. A Nurse can be arranged to visit, assess his needs and provide regular assistance with questions on diet, breathing exercises, etc. An aid can then come for 2-4 hours to provide assistance with dressing, shaving, ambulation (walking), and provide you time to run errands and see to your own needs without worrying over him. The nurse can be reassuring as a liaison with his doctor, to ask questions and arrange hospice care when the time is right.

First call your insurance company to ask what level of home care is covered, for how long, and how many visits per week. Ask if you can choose your own agency or if your insurance has a preferred network. Next call his Doctor and make an appointment. Write out a list of questions to make the most of the visit. This will be your chance to request home car assistance and ask about your husband's prognosis. Once care is arranged, the agency will contact you for the first appointment. The timing will be based on how much he can comfortably do for himself, and your needs as his caregiver. Do not put your needs on the back burner and compromise your health by not accepting help from others. It doesn't benefit him if you become ill. For more on home healthcare needs go to:

He should have certain paper work complete. A living will and durable power of attorney should be completed and on file with the hospital. If he has a will prepared you should have a copy and the original should be on file with an attorney. Even if the will is a simple one, he should have one in place to prevent any delays in settling his estate. If the bank accounts are in his name or they are joint accounts, consider opening accounts in your name alone to prevent any complications accessing the money you'll need. A statutory power of attorney can be prepared to allow you to complete financial transactions etc, in his place if he is incapacitated. If there is life insurance have a copy of the policy and who to call. If he is in charge of paying the bills make sure you have a current list of bills, due dates and balances. If you have a moderate to large estate, own your home and have investments you should consult with a lawyer to get advice on how to simplify the probate process.

Here are some basic forms and definitions that may help:

Statutory POA: look under Colorado statutory power of attorney.

Medical durable power of attorney and living will information and forms:

The forms are available at the end of the page as attachment a and b. For information on estate planning and probate go to:

A support group can help you cope, provide hope and support, help you prepare for what to expect by listening to other's stories and help you keep a balance between his needs and yours. Contact Well Spouse Association, the numbers are available at:

I hope this is helpful. If you have any follow up questions please ask them. I will be happy to continue our discussion until you have the answers you need.


Customer: replied 9 years ago.
ok we have done all that. in the past few mounths. everything is on file with our attorney

i just feel like copd and emphazemia is a non curable desease, so i dont understand the percetage that he has now is 20 percent enough to live a few more years. he also has an esphagus issue that is new and is being checked out. with a test that is set up for nov. 7
he just had an mri done on his lungs to see where he is at. so i still dont know what to expect and when.

COPD/emphysema is a progressive disease, but it does not progress at a predictable rate. The factors I mentioned above plus age, weight , sex, co-morbidity (other illnesses), heart disease, heredity, patient's outlook and motivation, family support, have all been proven to affect outcomes. His doctor was not relying on one number to predict his prognosis. It was a combination of several factors, and even still was an estimate.

Total lung capacity does not only refer to the lung's space, but also the patient's ability to inhale volumes of air. It also doesn't say how much air gets to the blood, which is vital. The air may go in the lung but the disease may also be preventing the absorption of the oxygen. This means a patient with 60% lung capacity may die from his disease process sooner than someone with a TLC of 20%.

The drop of 7% in TLC is a sign that the disease is progressing, and treatment is not effectively arresting it's progress. It is also a sign that he is fatigued and weakened by his disease so the muscles that support breathing will not let him breath in fully. By itself it does not predict how much longer he will live. The number itself doesn't mean he has "enough lung" to live for years or not enough to live more than one. What I said before was that a TLC of 20% does not rule out him surviving for any specific amount of time.

I apologize for missing the point of your question. I really though you wanted to know what to do over the next few months. I can tell you what total lung volume means by definition: the volume of air in the lungs after maximum inspiration; and I can tell you why his is low: copd makes the lungs stiff so they don't expand, fatigue from chronic illness and muscle weakness prevents full inspiration, possible changes in lung tissue may obstruct parts of the lung (ex. collapsed alveoli-air sacs-that occur with the disease process), and mucous production which may impeded airway; and I can give you Hospice's guidelines for determining prognosis in lung disease.

Hospice eligibility:

Hospice guidelines and information on "end stage" lung disease:

About half way down the page.

I hope something I've said has been helpful. Please let me know if there is more I can add. Best wishes, Christy


Christy Hammond and 6 other Health Specialists are ready to help you
Customer: replied 9 years ago.
yes, thank you so much and all of this is so overwhelming that i may have not been all clear but so you know i have many concerns like i said befor i dont know how to ask or what to ask so im so in the dark of it all. i do GREATLEY..appreciate all you have said here. thanks again
I am more than happy to help. I understand what you are going through and I would be happy to send you any resources you feel would help. Please let me know if you would like to read more about any particular subject (COPD, Pulmonary Function Testing, Hospice Care, support for you or your family). I appreciate your bonus and your kind words, thank you.